FreeRTOS running, SUCCESS!
to have cdc revceive_fs you must kick of reception , it will then be called in isr by usb stack when data will come from host, You start the rx by calling
uint8_t USBD_CDC_ReceivePacket(USBD_HandleTypeDef *pdev)
note that many hal driver and f/w will fail with freertos mainly because of usage hal_tick for time out or delay.
systick isr priority is
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